I apologize, I missed your link. But please don’t assume hostility for me missing a URL - I was clearly interested enough in the issue to do a Google search.

In any case, please see the comments on the HN post (linked by a sibling comment) for that. The issue is in fact wickedly complex, and it’s not clear (even among Bengali speakers) that this is a deficiency in Unicode (vs a deficiency in text entry and rendering software).